Enhanced Light‐Driven Hydrogen Production by Self‐Photosensitized Biohybrid Systems

Abstract Storage of solar energy as hydrogen provides a platform towards decarbonizing our economy. One emerging strategy for the production of solar fuels is to use photocatalytic biohybrid systems that combine the high catalytic activity of non‐photosynthetic microorganisms with the high light‐harvesting efficiency of metal semiconductor nanoparticles. However, few such systems have been tested for H 2 production. We investigated light‐driven H 2 production by three novel organisms, Desulfovibrio desulfuricans , Citrobacter freundii , and Shewanella oneidensis , self‐photosensitized with cadmium sulfide nanoparticles, and compared their performance to Escherichia coli . All biohybrid systems produced H 2 from light, with D. desulfuricans ‐CdS demonstrating the best activity overall and outperforming the other microbial systems even in the absence of a mediator. With this system, H 2 was continuously produced for more than 10 days with a specific rate of 36 μmol g dcw −1 h −1 . High apparent quantum yields of 23 % and 4 % were obtained, with and without methyl viologen, respectively, exceeding values previously reported.